Bristol Cove 1868. Orphaned and disfigured, Soot has always been stigmatized by his small fishing town. Hoping to one day better himself, he tries get in good with Captain Charles H. Pownall by babysitting his mistress, who carries a fantastical secret. Things get complicated when a merman washes up on the beach. After healing and befriending the mythical creature, the pair start to become close but complications arise when Soot becomes embroiled in a conflict between merfolk and humans, testing his loyalties, leading to an unforeseen historical tragedy.